Hamamelidis Folia and Hamamelidis Cortex of pharmacopoeias are the prepared leaves and bark respectively of this North American plant. Further processing provides Hamamelis Liquid and Dry Extracts and also Hamamelis Tincture. Being rich in tannins, these preparations were once widely used for their astringent properties in the external (and also internal) treatment of varicose veins, haemorrhoids, burns, and bruises, and also for their haemostatic activity (Remington et al. 1918, Ruddock c1937, Wade 1977). Although these tannin-containing preparations are still to be found as ingredients of some proprietary multi-ingredient products, an essentially tannin-free steam distillate of the twigs immersed in aqueous alcohol - known as Aqua Hamamelidis, Liquor Hamamelidis, Hamamelis Water, Distilled Witch Hazel, or just "Witch Hazel" - has largely replaced the tannin-containing preparations as an article of commerce. This preparation has a characteristic odour and in addition to water and alcohol (about 15% v/v), contains steam volatile extractives from the witch hazel, including α- & β-ionones, hexen-2-al, and 6-methyl-3,5-heptadiene-2-one (Wren 1988), which are known collectively as "hamamelis ketone".

It would appear that the supposed virtues of distilled witch hazel were invented by the pharmaceutical industry in the late 1800s when a proprietary preparation was originally introduced (Lloyd & Lloyd 1935). Subsequently, a non-proprietary preparation was made the subject of pharmacopoeial monographs in the US and in Britain (i.e. Liquor Hamamelidis), but then seemingly fell out of favour. The preparation appeared in a list of suggested deletions from the British Pharmacopoeia (Anon 1908) because it was considered to be "little more than a weak solution of alcohol". Shortly thereafter, Remington et al. (1918) stated that "This water was probably introduced into the British Pharmacopoeia and U.S. Pharmacopoeia IX on account of the large demand for it which has grown out of the wide advertisements of a certain proprietary medicine, and the universally recognized need in American families for an embrocation which appeals to the psychic influence of faith. As the tannic acid of hamamelis bark does not come over into the distillate the water is therapeutically a mixture of water and alcohol, the volatile oil being found in too minute a proportion to possess any therapeutic value." Remington et al. (1918) also stated that when injected into frogs in high volumes, Aqua Hamamelidis showed no more pharmacological activity than would be expected from water. Nevertheless, this preparation continues to be widely recommended as a soothing, astringent application for sprains and bruises, as a haemostat for small superficial wounds, and as an application for minor skin irritation, authors (see Wade 1977, Wren 1988) inadvertently perpetuating the notion that distilled witch hazel is endowed with the healing properties associated with the tannin-containing preparations. Interestingly, a monograph for Liquor Hamamelidis appeared in the British Pharmaceutical Codex until 1973.

Hamamelis Virginiana Extract [CAS RN 84696-19-5]a, which is an extract of the bark, leaves and twigs, is a recognised European cosmetic product ingredient identified as having an "astringent/soothing/skin conditioning/hair conditioning" function. Hamamelis Virginiana Distillate and Hamamelis Virginiana Water [both having also been assigned CAS RN 84696-19-5]a, which are aqueous solutions containing volatile extractives obtained by the distillation of the twigs, bark and leaves, and of the flowers respectively, are similarly recognised European cosmetic product ingredients supposedly having the same "astringent/soothing/skin conditioning/hair conditioning" function (Standing Committee on Cosmetic Products 2006).

Korting et al. (1993), using UV-induced erythema and skin stripping in human volunteers, demonstrated mild anti-inflammatory activity of a hamamelis distillate (standardised for hamamelis ketone content) presented in a phosphatidylcholine-containing vehicle. However, a four-fold increase in the concentration of hamamelis ketone did not increase the observed activity. In a study investigating a similar preparation in patients with moderately severe atopic eczema, Korting et al. (1995) found a hamamelis distillate-containing cream to have no more effect on itching, erythema, and scaling than vehicle alone. Later, Hughes-Formella et al. (1998) also demonstrated a low level of anti-inflammatory activity against UV-induced erythema in topical preparations containing hamamelis distillate, observing in addition (Hughes-Formella et al. 2002) that preparations from different suppliers seemed to differ in their potency.

Witch hazel has been reported to cause contact dermatitis but it is difficult in some of the cases to ascertain exactly which preparation is the putative sensitiser. Early mention of an adverse effect of a witch hazel preparation on skin was made by White (1896, 1897, 1903). Subsequent reference to White's observation was made by Touton (1932), Weber (1937), and Genner & Bonnevie (1938). Duke-Elder (1965) made brief reference to "hamamelis" being one of the less common causes of allergic contact dermato-conjunctivitis. Granlund (1994) described a case of a non-atopic woman who developed contact allergy to an unspecified proprietary "eye-gel" and reacted when patch tested with the "witch hazel distillate" it contained. Five control subjects did not react to the eye gel. Bruynzeel et al. (1992) observed four patients from a series of 1032 who reacted on patch testing with a proprietary ointment containing "Hamamelis extract" for treating haemorrhoids, namely Hamametum™. No control tests were carried out so the possibility remains that these patients were reacting to other components of the ointment base. Meneghini (1970), on the other hand, obtained no positive patch test reactions to "Hamamelis virg. 10% in petrolatum" in a series of 280 consecutive eczema patients.